hachu — xboard-compatible engine for Chu Shogi and other variants
Descriptionhachu is a program that plays several shogi and chess variants, currently sho shogi, chu shogi, dai shogi, makruk and shatranj. In the future it might play more, and still larger shogi variants, in particular tenjiku shogi.
HaChu uses the xboard/winboard chess-engine protocol to communicate. It thus can use XBoard as a graphical interface for the variants also supported by the latter. Only XBoard 4.8 and later support chu shogi, but sho shogi should already work under XBoard 4.7, and Makruk and Shatranj under much older versions. Dai shogi is not supported by XBoard yet.
See xboard(6) for instructions about how to use hachu through xboard. To start up quickly, you just need the command: xboard -fcp hachu. You can then use XBoard's New Variant dialog to select the variant you want to play. To play chu shogi, it is essential that XBoard's 'show target squares' option is switched on; otherwise the two-step lion moves can not be entered.
Normally XBoard will use western-style chess symbols to represent the pieces. But HaChu comes with a set of piece images in the shape of the Japenese kanji for the names of the chu-shogi pieces. These can be used in XBoard to get an oriental-style board display. A settings file for configuring XBoard to use these pieces is also included with HaChu, so that you can use the command xboard @chu to start XBoard with HaChu for oriental-style chu-shogi.
- INTERACTIVE OPTIONS
- HaChu supports some options that can only be set interactively, though XBoard's engine settings menu dialog. These include an option for solving tsume problems (checkmate problems where the winning side is only allowed to play checking moves). There are also options to adapt it to various versions of the chu-shogi rules: whether you can only promote on entering the promotion zone, or whether moves inside or out of the zone (after one move delay) can also be used for promotion, and whether repeats should be strictly forbidden, or only avoided like other losing moves.